The U.S. Air Force's SBIRS Geo-3 satellite is scheduled to launch atop a United Launch Alliance (ULA) Atlas V rocket Friday (Jan. 20) at 7:42p.m. EST (0042 GMT on Jan. 21). Watch the liftoff live in the window below, beginning at 7:22 p.m. EST (0022 GMT), courtesy of ULA:
"SBIRS [short for Space Based Infrared System], considered one of the nation's highest-priority space programs, is designed to provide global, persistent, infrared surveillance capabilities to meet 21st-century demands in four national security mission areas, including: missile warning, missile defense, technical intelligence and battlespace awareness," ULA representatives wrote in a mission description.
The launch was originally scheduled for Thursday night (Jan. 19) but was pushed to Friday because of a sensor issue and the intrusion of an aircraft into restricted airspace.
The first SBIRS Geo satellite launched in 2011, and SBIRS Geo-2 reached orbit in 2013.
You can also watch the liftoff directly via ULA's YouTube channel here: https://www.youtube.com/watch?v=Vi2_yIFylxo
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